.header {
  z-index: 2;
  position: fixed;
  width: 100%;
  height: 70px;
  line-height: 70px;
  // min-width: 1300px;
  background-color: white;
  box-shadow: 3px 2px 5px rgb(240, 240, 240);

  .margins {
    max-width: 1500px;
    padding: 0px 80px 0 80px;
    margin: 0 auto;

    .logo {
      float: left;

      img {
        width: 35px;
        vertical-align: -9px;
      }

      .title {
        font-family: 楷体, serif;
        color: rgb(100, 100, 100);
        font-size: 27px;
      }
    }

    .menu {
      float: right;
      font-size: 16px;

      .item {
        width: 90px;
        transition: .3s;
        text-align: center;
        color: rgb(60, 60, 60);
        display: inline-block; // 禁止换行
      }

      .item:hover {
        color: black;
        transition: .3s;
        background-color: rgb(251, 251, 251);
      }
    }

    a.active .item {
      background-color: rgb(247, 247, 247);
    }

  }
}